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arXiv · 1408.2281

Comparing DNR and WWKL

Klaus Ambos-Spies·Bjørn Kjos-Hanssen·Steffen Lempp·Theodore A. Slaman
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Abstract

In Reverse Mathematics, the axiom system DNR, asserting the existence of diagonally non-recursive functions, is strictly weaker than WWKL$_0$ (weak weak König's Lemma).

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Klaus Ambos-Spies, Bjørn Kjos-Hanssen, Steffen Lempp, Theodore A. Slaman. 2014-08-10. Comparing DNR and WWKL. https://doi.org/10.2178/jsl%2F1102022212

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